MG Sports Cars

I like the look of 4/5/6 pt harnesses -- but, the Miata seats aren't really wide enough to run slots through the top area for the shoulder straps. I could do velcro type retainers on the sides of the seats like Bill Guzman has on his roadster, but let's face it, my shoulders aren't aren't as wide as his! I'm concerned that in a collision the shoulder harneses would slide out/over my shoulders making them ineffective. I'm thinking I have two choices --
1. Punt (drop back to regular 3-pt)
2. Consider a harness like the Schroth ones like these. The shoulder harness comes together so could use a single slot in the middle. Plus the one with the inertia reel would make them more convenient for a daily driver.

Anyone use these? Does the fact that they come together right behind your neck get annoying?

Any other suggestions?

Rob, first of all don't worry nothing is as wide as Bill G. ;-) I'm using a standard 5 point harness in my car, but the shoulder belts attach to a common point just behind the seat on the roll bar and no, they don't seem to feel unusual even though the come together just a few inches behind my back. That Schroth belt looks neat and I like the inertia reel feature as well as it would allow some movement in the seat, but only if the seat had no head rest and the common belt could run straight back from the center of your body. Really can't see that belt running at an angle back to the stock MGB mounting location. It wouldn't be much better than a standard 3 point belt if you did that. Unless you plan on doing some serious autocrossing in the car I think I'd just go for a standard 3 point belt and use a torso strap when you want to autocross. That's what I used originally with the stock seats in my car and it worked pretty good.
If you're worried about a 4 point system slipping over your shoulders you can add a sternum protector link easily that will hold the shoulder straps together across your chest for under $20 [www.speedwaymotors.com]
Using a standard 5 point latch system you can run with any combination of belts that you like and is comfortable for daily driving, a lap belt with one shoulder belt similar to a 3 point system, both shoulder belts, or the whole lot including the crotch belt and sternum protector. Your choice.

If I go with this type of belt, I'd attach to a rollbar -- similar to this but I'm planning for a double hoop type roll bar. Plan is for each hoop to go to the floor with a cross piece about the height of the slot in the seat for the harness shoulder straps. Two braces from the main hoop back to the corner of the battery shelf where it meets the panel that seperates cockpit from trunk. Won't be able to mock it up to be sure I can do that without interfering with the top, but that's the idea I have in mind.

Good to know the belts coming together doesn't get annoying.

With respect to using a std 5-pt & latching just the lap & one shoulder being similar to 3-point -- I'm not sure you'll get the same protection. The design of a 3-pt helps keep your body from rotating out from behind the seatbelt. With the 5-pt shoulder strap going basically straight down, I think you won't get that protection.

I want this look, but I'm probably going to do a regular 3-pt on the passenger side since they'll fit kids better. Ideally I'll come up with a way to have both on that side w/o it looking hokey.

Rob, fitting standard 3 point inertia type belts with a roll bar can be a problem if you intend to use the original mounting points. I did but find that I have to pull the passenger side belt mostly straight up instead of forward to get it to unwind. Not a big deal and would be easier if I'd used an aftermarket belt which is adjustable for angle of installation on the reel. I used a 5 point harness on the driver's side only in red and then found a matching color 3 point belt for the passenger side. I added home made shoulder pads with a MG logo patch sewn to each and the combination did look pretty well matched after that.

Rob, I use Schroth belts with Miata seats and one hole through the middle of the seat back. I do not have any problems at all. I am not sure the inertia reel is of any value. Cutting the hole in the seat is easy. No steel to cut only foam. I made a fiberglass insert for the seat opening. I will try to get some pictures. Making the inserts was by far the biggest part of the job. The one problem with this style of belt is adjusting it all the time for different passengers. I am thinking about using a sholder belt for the passenger side because most people give up on adjusting the belt properly.

Dale

Dale, that's great to hear. I'd defintely like to see pics of the fiberglass insert you're talking about. Not sure I'm following what that's for.

With respect to the inertia reel, you don't think that'd make it more comfortable in a frequent driver? I'm thinking about the occasional need to open the glove box or reach for something behind the seats.

Rob

Is the fiberglass insert to protect the belts from chafing on the seat's metal frame?

I cut slots in my Fiero seats for shoulder harnesses - the Mr.Mike's covers (when ordered with slots for same) have extra tabs of leather/vinyl on each side of the cover that fold in to protect the belt and finish off the appearance..

Just curious.

After cutting the hole in the foam you need a way to finish the the hole in the seat cover and line the inside of the hole in the foam. I did not have any extra material to sew a liner into the seat cover so I made the fiberglass pieces. They work well but as I said it was a lot of work making them. I thought about coming up with a kit and selling them. I will get a couple of pictures for you.

dale

I attached some pictures of my seat, the mold I made and an unfinished protortype. After looking again at the picture above with the red seats I would consider doing what he did because the belt passes through the seat at a little higher position on the seat back. You do not want the seat belt to push you down in a crash. For a tall person mine are marginal but they work fine for me. I do not recall what the steel structure looks like in the seat in that area so I am not sure how much trouble that would be.

Hi Rob, there's another rare type of Miata seat found in the '94-'95 Merlot Edition only. They have adjustable headrest, that's the seat I decided to go with in my car as I believe the separate headrest is more era appropriate.

Yeah, those probably would have been better. Evan Amaya has them on his car too. They probably would have worked better with regular shoulder harnesses but I think they'd still be a bit tight as its still a realatively narrow seat up top. Anyway, I've already bought my seats & MrMikes is making the covers now so I'm going to stick with the regular Miata ones.

Thanks for the info on the years though -- I had no idea what years had those seats.